Patent · US Expired

Method of making a composite filter

US5024764A · kind A · utility

38Cited by
6References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 17, 1989
Grant dateJun 18, 1991
Priority date
Expiry dateMar 17, 2009

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC02F2201/006
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A composite cartridge-type filter effective to substantially reduce low but hazardous concentrations of lead in drinking water to acceptable levels utilizes a porous activated carbon block filter and a powdered deionizing resin which is converted to an ion exchange resin in situ and during use of the filter. The method of operation of the filter results in a substantially extended life for lead removal as compared to similar disposable cartridge filters. The composite filter is also effective in removing dissolved metals which are leached from the soluble ash fraction of the carbon block itself. Powdered deionizing resin, having a greatly enhanced active surface area as compared to the resin beads from which it is formed, is formed by fracturing the resin beads in situ in a slurry filling and drying process which provides a stable packed resin bed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.